Turbine blades on jets questions

[Anthony2107]

There are two types of turbine blades in the jet engines. One is the "impulse " type turbine,which relies upon the nozzle vanes to convert the combustion gas static pressure to high velocity jets, and are shaped to produce a large deflection of gas resulting in a tangential force by flow direction change.
The other one is the "reaction" type shaped to provide a pressure drop and velocity increase across the blades thereby producing tangential force as well.
But wait a cotton pickin' minute, which one is more efficient though ? ( more work for less fuel )
To the Boeing jocks - Which one does Rolls Royce use ?

[Trash Hauler]

I am not sure which one was claimed to be more efficient.

The third option that you did not mention is the hybrid "impulse/reaction' from my reading most modern engines (RR, P&W, GE etc) utilise turbine blades that have facets of noth principles in their design.

Cheers

[Anthony2107]

TH

I intentionally did not mention the third one because the hybrid are a mix of the two therefore for obvious reasons getting the best of both designs.
I just want to know which of the two are more efficient and if any of these two are used independently in any engines? Esp R.R.

[exeng]

I was taught many years ago as an engineering apprentice that 'Reaction' blades were more efficient. However I believe that modern blades are a combination of both reaction and impulse.


Regards
Exeng

[Anthony2107]

Thanks Exeng - that'll do me.